This invention relates to a method and associated system for manufacturing a runner for use alone or with a pallet in the storage and/or transport of goods and, more particularly, to such a system and method for manufacturing a recyclable and reinforced runner and pallet design.
For many years, various types of objects have been used to separate and support loads that are stored and transported generally in a stacked arrangement. The equipment that is primarily used for performing this stacking arrangement is a front end loader, lift truck or fork lift truck which raises the individual loads so that they can be stacked one on top of the other or on a rack. To separate the loads from each other, off the rack or off of the floor, a pallet, riser or runner is positioned beneath the load so as to allow space for the insertion of the forks of the lift truck or the like for moving and positioning the loads for storage or transportation. Generally, the load supporting pallets are mainly made from wood and consist of platforms having parallel runners longitudinally and/or transversely secured to the underside by nails, staples, strapping or other suitable fasteners.
While such wooden pallets in the past have been found to be satisfactory in many regards for their intended use in transporting and storage of materials and articles from one location to another, there are many disadvantages associated with wooden pallets. Increased environmental awareness has become a significant factor in the packaging, transportation and shipping industries. Wood is difficult to readily recycle and, hence, many wood packaging or pallet components are finally disposed of in land fills. However, available land fill sites are becoming full and, if available, require significant fees for dumping such materials.
For the international shipment of goods, wooden pallets present additional environmental problems because they tend to serve as hosts for germs and bugs. Wooden pallets are often quarantined or burned upon arrival in the destination country according to governmental regulations or general precautionary practices to avoid the spread of undesirable insects, bugs or germs.
To avoid some of the objections to the use of wood pallets, alternative pallet designs utilize materials such as corrugated paperboard, scrapped paperboard, plastics, aluminum and other materials. While solving certain problems associated with wood pallets, pallets and runners from non-wood materials often have significant deficiencies. While non-wood pallets may be light weight and inexpensive for some applications, their strength and rigidity under static and dynamic loading is insufficient to permit wide spread general use for all types of goods. Such non-wood pallets often have excessive deflection and lack beam strength which causes their sagging under loads thereby making the handling, stacking and racking of the pallets impractical and even dangerous. Many so called improved pallet designs do not offer the strength necessary to withstand buckling, crushing or compression when placed upon a rack under a load.
A solution to many of these problems is disclosed in applicant's own prior U.S. Pat. No. 6,095,061 which discloses a reinforced, rackable and recyclable pallet and runner. The pallet/runner design disclosed in the '061 patent is light weight and provides significant strength and increased load bearing capability and resistance to compression and crushing while still providing the significant advantages of being entirely processable in a paperboard recycling system or the like for convenient, economical and ecological disposal.
The '061 patent discloses a pallet which includes at least two spaced generally parallel runners and each of the runners is constructed of a number of layers of double wall or double face corrugated paperboard glued together in face-to-face orientation with the flutes of the corrugations being generally aligned in a generally vertical direction. Each of the runners also includes at least one generally vertically oriented reinforcing insert positioned between adjacent layers of the corrugated paperboard.
One method for manufacturing such a runner is to laminate layers of corrugated paperboard one on top of another in face-to-face relation with the reinforcing insert or inserts positioned therein. The various layers of paperboard and reinforcing insert may be adhered in a face-to-face relation by an adhesive commonly known in the industry to form the billet. Typically, the billet of sheets or layers of corrugated paperboard and reinforcing insert is then stacked with similar billets one on top of another, typically four to six high, and compressed in an effort to bond the various layers in the respective billets to one another. After compressing the multiple billets in a single batch process, the individual billets are then sawed or cut into the individual runners for ultimate use or incorporation into a pallet.
However, applicant discovered that during the production of the runners according the '061 pallet and the above described method, frequently the adjacent layers of paperboard separate one from another and/or from the reinforcing insert particularly at the lateral ends of the runners. Increased pressure on the multiple billets, increased adhesive volume and alternative adhesives did not significantly improve the situation or minimize the occurrence of runner separation. Therefore, a need exists for an improved method and associated system for manufacturing paperboard pallet runners that have at least one reinforcing insert that avoids the problem of delaminating or separation of the adjacent layers of glued materials.